The combination operation of this innovative processing sequence embodies scattered excerpts of the prior art in a synergistic relationship particularly contributing to efficient reduced crude processing.
The reaction of steam with coke on solid substrates was the subject of a paper by T. Y. Yan and M. P. Rosynek given before the American Chemical Society in September 1979, Washington Meeting. In this paper reference is made to the catalytic processing of heavy oil and residua over cracking catalysts and various schemes for removing deposited coke using steam and oxygen by referring to U.S. Pat. Nos. 3,691,063, 3,726,791 and 3,983,030.
U.S. Pat. No. 3,433,732 discloses steam reforming a heated hydrocracking catalyst to produce hydrogen and regenerate the catalyst at the same time.
U.S. Pat. No. 2,888,395 discloses a catalytic coking process whereby coked catalyst is steam reformed to produce hydrogen.
U.S. Pat. No. 2,702,267 discloses the mixing of spent and regenerated catalyst particles in a soaking zone and using hot regeneration product gases as the fluidizing and stripping gas in the soaking zone. The catalyst is regenerated at a temperature above 1400.degree. F. with a mixture of steam and high purity oxygen comprising no more than 10 vol. % of nitrogen to produce a flue gas product comprising hydrogen, carbon oxides and excess steam. When the mixture of steam and high purity oxygen is used as the regenerating medium, the principal reactions are:
2C+O.sub.2 .fwdarw.2CO PA0 C+O.sub.2 --CO.sub.2 (Exoth) PA0 C+CO.sub.2 --2CO (Endo) PA0 CO+H.sub.2 O.fwdarw.CO.sub.2 +H.sub.2 PA0 C+H.sub.2 O--CO+H.sub.2 (Endo) PA0 CO+H.sub.2 O--CO.sub.2 +H.sub.2 (Exoth)
To insure a high yield of hydrogen, more steam than oxygen is used.
British Patent 2001545 describes a two stage regeneration operation controlled so that only partial regeneration of catalyst particles occurs in the first zone and the catalyst particles are not heated excessively and a CO flue gas is produced.
The use of CO.sub.2 or steam with an oxygen containing stream is disclosed whereby a flue gas of high CO or CO-hydrogen concentration is obtained. Such a steam is valuable for use in water-gas shift to produce hydrogen. The regeneration zones are positioned one above the other so that partially regenerated catalyst may flow from the upper zone to the lower zone by gravity. Regeneration gas used in the upper zone may be either O.sub.2 +steam, O.sub.2 +CO.sub.2, O.sub.2 +steam+CO.sub.2 depending on the composition of flue gas particularly desired. Preferably the gas charged to the second stage of regeneration is air.
U.S. Pat. No. 4,244,811 discloses the catalytic cracking of a hydrocarbon feed in the presence of water and subjecting deactivated catalyst with coke deposits to gasification conditions consisting of partial oxidative combustion to produce gas rich in CO or with the addition of steam to produce a gas rich in hydrogen or both CO+H.sub.2.
U.S. Pat. No. 3,691,063 relates to a residual fuel oil hydrocracking process wherein a residuum feed is subjected to metals removal in a guard case containing an acid catalyst along with asphaltenes. The guard catalyst is regenerated with steam and oxygen to maximize hydrogen production by partial oxidation of asphaltenes. The hydrogen produced is used in the hydrocracking step. Hydrogen plus carbon monoxide from the guard chamber regeneration is fed to a two stage water gas shift operation where steam is reacted with the carbon monoxide to form additional hydrogen and carbon dioxide.
U.S. Pat. No. 3,726,791 relates to a process where high Conradson carbon feeds are coked to lay down carbon deposits on a gasification catalyst and the coked catalyst is steam gasified to produce hydrogen.
U.S. Pat. No. 3,983,030 relates to a process for demetalation and desulfurization of residua and deposited coke gasification with steam and free oxygen to produce producer gas and regenerate a porous refractory oxide used to demetallize and desulfurize the residual.